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2017-10-11bpf: remove redundant variable old_flagsColin Ian King
Variable old_flags is being assigned but is never read; it is redundant and can be removed. Cleans up clang warning: Value stored to 'old_flags' is never read Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10bpf: write back the verifier log buffer as it gets filledJakub Kicinski
Verifier log buffer can be quite large (up to 16MB currently). As Eric Dumazet points out if we allow multiple verification requests to proceed simultaneously, malicious user may use the verifier as a way of allocating large amounts of unswappable memory to OOM the host. Switch to a strategy of allocating a smaller buffer (1024B) and writing it out into the user buffer after every print. While at it remove the old BUG_ON(). This is in preparation of the global verifier lock removal. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10bpf: move instruction printing into a separate fileJakub Kicinski
Separate the instruction printing into a standalone source file. This way sneaky code from tools/ can compile it in directly. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10bpf: move global verifier log into verifier environmentJakub Kicinski
The biggest piece of global state protected by the verifier lock is the verifier_log. Move that log to struct bpf_verifier_env. struct bpf_verifier_env has to be passed now to all invocations of verbose(). Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-10bpf: encapsulate verifier log state into a structureJakub Kicinski
Put the loose log_* variables into a structure. This will make it simpler to remove the global verifier state in following patches. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Reviewed-by: Simon Horman <simon.horman@netronome.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2017-10-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Fix object leak on IPSEC offload failure, from Steffen Klassert. 2) Fix range checks in ipset address range addition operations, from Jozsef Kadlecsik. 3) Fix pernet ops unregistration order in ipset, from Florian Westphal. 4) Add missing netlink attribute policy for nl80211 packet pattern attrs, from Peng Xu. 5) Fix PPP device destruction race, from Guillaume Nault. 6) Write marks get lost when BPF verifier processes R1=R2 register assignments, causing incorrect liveness information and less state pruning. Fix from Alexei Starovoitov. 7) Fix blockhole routes so that they are marked dead and therefore not cached in sockets, otherwise IPSEC stops working. From Steffen Klassert. 8) Fix broadcast handling of UDP socket early demux, from Paolo Abeni. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (37 commits) cdc_ether: flag the u-blox TOBY-L2 and SARA-U2 as wwan net: thunderx: mark expected switch fall-throughs in nicvf_main() udp: fix bcast packet reception netlink: do not set cb_running if dump's start() errs ipv4: Fix traffic triggered IPsec connections. ipv6: Fix traffic triggered IPsec connections. ixgbe: incorrect XDP ring accounting in ethtool tx_frame param net: ixgbe: Use new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag Revert commit 1a8b6d76dc5b ("net:add one common config...") ixgbe: fix masking of bits read from IXGBE_VXLANCTRL register ixgbe: Return error when getting PHY address if PHY access is not supported netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1' netfilter: SYNPROXY: skip non-tcp packet in {ipv4, ipv6}_synproxy_hook tipc: Unclone message at secondary destination lookup tipc: correct initialization of skb list gso: fix payload length when gso_size is zero mlxsw: spectrum_router: Avoid expensive lookup during route removal bpf: fix liveness marking doc: Fix typo "8023.ad" in bonding documentation ipv6: fix net.ipv6.conf.all.accept_dad behaviour for real ...
2017-10-09Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nfDavid S. Miller
Pablo Neira Ayuso says: ==================== Netfilter/IPVS fixes for net The following patchset contains Netfilter/IPVS fixes for your net tree, they are: 1) Fix packet drops due to incorrect ECN handling in IPVS, from Vadim Fedorenko. 2) Fix splat with mark restoration in xt_socket with non-full-sock, patch from Subash Abhinov Kasiviswanathan. 3) ipset bogusly bails out when adding IPv4 range containing more than 2^31 addresses, from Jozsef Kadlecsik. 4) Incorrect pernet unregistration order in ipset, from Florian Westphal. 5) Races between dump and swap in ipset results in BUG_ON splats, from Ross Lagerwall. 6) Fix chain renames in nf_tables, from JingPiao Chen. 7) Fix race in pernet codepath with ebtables table registration, from Artem Savkov. 8) Memory leak in error path in set name allocation in nf_tables, patch from Arvind Yadav. 9) Don't dump chain counters if they are not available, this fixes a crash when listing the ruleset. 10) Fix out of bound memory read in strlcpy() in x_tables compat code, from Eric Dumazet. 11) Make sure we only process TCP packets in SYNPROXY hooks, patch from Lin Zhang. 12) Cannot load rules incrementally anymore after xt_bpf with pinned objects, added in revision 1. From Shmulik Ladkani. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-09netfilter: xt_bpf: Fix XT_BPF_MODE_FD_PINNED mode of 'xt_bpf_info_v1'Shmulik Ladkani
Commit 2c16d6033264 ("netfilter: xt_bpf: support ebpf") introduced support for attaching an eBPF object by an fd, with the 'bpf_mt_check_v1' ABI expecting the '.fd' to be specified upon each IPT_SO_SET_REPLACE call. However this breaks subsequent iptables calls: # iptables -A INPUT -m bpf --object-pinned /sys/fs/bpf/xxx -j ACCEPT # iptables -A INPUT -s 5.6.7.8 -j ACCEPT iptables: Invalid argument. Run `dmesg' for more information. That's because iptables works by loading existing rules using IPT_SO_GET_ENTRIES to userspace, then issuing IPT_SO_SET_REPLACE with the replacement set. However, the loaded 'xt_bpf_info_v1' has an arbitrary '.fd' number (from the initial "iptables -m bpf" invocation) - so when 2nd invocation occurs, userspace passes a bogus fd number, which leads to 'bpf_mt_check_v1' to fail. One suggested solution [1] was to hack iptables userspace, to perform a "entries fixup" immediatley after IPT_SO_GET_ENTRIES, by opening a new, process-local fd per every 'xt_bpf_info_v1' entry seen. However, in [2] both Pablo Neira Ayuso and Willem de Bruijn suggested to depricate the xt_bpf_info_v1 ABI dealing with pinned ebpf objects. This fix changes the XT_BPF_MODE_FD_PINNED behavior to ignore the given '.fd' and instead perform an in-kernel lookup for the bpf object given the provided '.path'. It also defines an alias for the XT_BPF_MODE_FD_PINNED mode, named XT_BPF_MODE_PATH_PINNED, to better reflect the fact that the user is expected to provide the path of the pinned object. Existing XT_BPF_MODE_FD_ELF behavior (non-pinned fd mode) is preserved. References: [1] https://marc.info/?l=netfilter-devel&m=150564724607440&w=2 [2] https://marc.info/?l=netfilter-devel&m=150575727129880&w=2 Reported-by: Rafael Buchbinder <rafi@rbk.ms> Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-10-07bpf: Append prog->aux->name in bpf_get_prog_name()Martin KaFai Lau
This patch makes the bpf_prog's name available in kallsyms. The new format is bpf_prog_tag[_name]. Sample kallsyms from running selftests/bpf/test_progs: [root@arch-fb-vm1 ~]# egrep ' bpf_prog_[0-9a-fA-F]{16}' /proc/kallsyms ffffffffa0048000 t bpf_prog_dabf0207d1992486_test_obj_id ffffffffa0038000 t bpf_prog_a04f5eef06a7f555__123456789ABCDE ffffffffa0050000 t bpf_prog_a04f5eef06a7f555 Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07bpf: Change bpf_obj_name_cpy() to better ensure map's name is init by 0Martin KaFai Lau
During get_info_by_fd, the prog/map name is memcpy-ed. It depends on the prog->aux->name and map->name to be zero initialized. bpf_prog_aux is easy to guarantee that aux->name is zero init. The name in bpf_map may be harder to be guaranteed in the future when new map type is added. Hence, this patch makes bpf_obj_name_cpy() to always zero init the prog/map name. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07bpf: fix liveness markingAlexei Starovoitov
while processing Rx = Ry instruction the verifier does regs[insn->dst_reg] = regs[insn->src_reg] which often clears write mark (when Ry doesn't have it) that was just set by check_reg_arg(Rx) prior to the assignment. That causes mark_reg_read() to keep marking Rx in this block as REG_LIVE_READ (since the logic incorrectly misses that it's screened by the write) and in many of its parents (until lucky write into the same Rx or beginning of the program). That causes is_state_visited() logic to miss many pruning opportunities. Furthermore mark_reg_read() logic propagates the read mark for BPF_REG_FP as well (though it's readonly) which causes harmless but unnecssary work during is_state_visited(). Note that do_propagate_liveness() skips FP correctly, so do the same in mark_reg_read() as well. It saves 0.2 seconds for the test below program before after bpf_lb-DLB_L3.o 2604 2304 bpf_lb-DLB_L4.o 11159 3723 bpf_lb-DUNKNOWN.o 1116 1110 bpf_lxc-DDROP_ALL.o 34566 28004 bpf_lxc-DUNKNOWN.o 53267 39026 bpf_netdev.o 17843 16943 bpf_overlay.o 8672 7929 time ~11 sec ~4 sec Fixes: dc503a8ad984 ("bpf/verifier: track liveness for pruning") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Edward Cree <ecree@solarflare.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07bpf: add helper bpf_perf_prog_read_valueYonghong Song
This patch adds helper bpf_perf_prog_read_cvalue for perf event based bpf programs, to read event counter and enabled/running time. The enabled/running time is accumulated since the perf event open. The typical use case for perf event based bpf program is to attach itself to a single event. In such cases, if it is desirable to get scaling factor between two bpf invocations, users can can save the time values in a map, and use the value from the map and the current value to calculate the scaling factor. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07bpf: add helper bpf_perf_event_read_value for perf event array mapYonghong Song
Hardware pmu counters are limited resources. When there are more pmu based perf events opened than available counters, kernel will multiplex these events so each event gets certain percentage (but not 100%) of the pmu time. In case that multiplexing happens, the number of samples or counter value will not reflect the case compared to no multiplexing. This makes comparison between different runs difficult. Typically, the number of samples or counter value should be normalized before comparing to other experiments. The typical normalization is done like: normalized_num_samples = num_samples * time_enabled / time_running normalized_counter_value = counter_value * time_enabled / time_running where time_enabled is the time enabled for event and time_running is the time running for event since last normalization. This patch adds helper bpf_perf_event_read_value for kprobed based perf event array map, to read perf counter and enabled/running time. The enabled/running time is accumulated since the perf event open. To achieve scaling factor between two bpf invocations, users can can use cpu_id as the key (which is typical for perf array usage model) to remember the previous value and do the calculation inside the bpf program. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Alexei Starovoitov <ast@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-07bpf: perf event change needed for subsequent bpf helpersYonghong Song
This patch does not impact existing functionalities. It contains the changes in perf event area needed for subsequent bpf_perf_event_read_value and bpf_perf_prog_read_value helpers. Signed-off-by: Yonghong Song <yhs@fb.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-06Merge branch 'core-watchdog-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull watchddog clean-up and fixes from Thomas Gleixner: "The watchdog (hard/softlockup detector) code is pretty much broken in its current state. The patch series addresses this by removing all duct tape and refactoring it into a workable state. The reasons why I ask for inclusion that late in the cycle are: 1) The code causes lockdep splats vs. hotplug locking which get reported over and over. Unfortunately there is no easy fix. 2) The risk of breakage is minimal because it's already broken 3) As 4.14 is a long term stable kernel, I prefer to have working watchdog code in that and the lockdep issues resolved. I wouldn't ask you to pull if 4.14 wouldn't be a LTS kernel or if the solution would be easy to backport. 4) The series was around before the merge window opened, but then got delayed due to the UP failure caused by the for_each_cpu() surprise which we discussed recently. Changes vs. V1: - Addressed your review points - Addressed the warning in the powerpc code which was discovered late - Changed two function names which made sense up to a certain point in the series. Now they match what they do in the end. - Fixed a 'unused variable' warning, which got not detected by the intel robot. I triggered it when trying all possible related config combinations manually. Randconfig testing seems not random enough. The changes have been tested by and reviewed by Don Zickus and tested and acked by Micheal Ellerman for powerpc" * 'core-watchdog-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits) watchdog/core: Put softlockup_threads_initialized under ifdef guard watchdog/core: Rename some softlockup_* functions powerpc/watchdog: Make use of watchdog_nmi_probe() watchdog/core, powerpc: Lock cpus across reconfiguration watchdog/core, powerpc: Replace watchdog_nmi_reconfigure() watchdog/hardlockup/perf: Fix spelling mistake: "permanetely" -> "permanently" watchdog/hardlockup/perf: Cure UP damage watchdog/hardlockup: Clean up hotplug locking mess watchdog/hardlockup/perf: Simplify deferred event destroy watchdog/hardlockup/perf: Use new perf CPU enable mechanism watchdog/hardlockup/perf: Implement CPU enable replacement watchdog/hardlockup/perf: Implement init time detection of perf watchdog/hardlockup/perf: Implement init time perf validation watchdog/core: Get rid of the racy update loop watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage watchdog/sysctl: Clean up sysctl variable name space watchdog/sysctl: Get rid of the #ifdeffery watchdog/core: Clean up header mess watchdog/core: Further simplify sysctl handling watchdog/core: Get rid of the thread teardown/setup dance ...
2017-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Just simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-05Merge tag 'pm-4.14-rc4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fix from Rafael Wysocki: "This fixes a code ordering issue in the main suspend-to-idle loop that causes some "low power S0 idle" conditions to be incorrectly reported as unmet with suspend/resume debug messages enabled" * tag 'pm-4.14-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / s2idle: Invoke the ->wake() platform callback earlier
2017-10-06Merge branch 'pm-sleep'Rafael J. Wysocki
* pm-sleep: PM / s2idle: Invoke the ->wake() platform callback earlier
2017-10-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking fixes from David Miller: 1) Check iwlwifi 9000 reorder buffer out-of-space condition properly, from Sara Sharon. 2) Fix RCU splat in qualcomm rmnet driver, from Subash Abhinov Kasiviswanathan. 3) Fix session and tunnel release races in l2tp, from Guillaume Nault and Sabrina Dubroca. 4) Fix endian bug in sctp_diag_dump(), from Dan Carpenter. 5) Several mlx5 driver fixes from the Mellanox folks (max flow counters cap check, invalid memory access in IPoIB support, etc.) 6) tun_get_user() should bail if skb->len is zero, from Alexander Potapenko. 7) Fix RCU lookups in inetpeer, from Eric Dumazet. 8) Fix locking in packet_do_bund(). 9) Handle cb->start() error properly in netlink dump code, from Jason A. Donenfeld. 10) Handle multicast properly in UDP socket early demux code. From Paolo Abeni. 11) Several erspan bug fixes in ip_gre, from Xin Long. 12) Fix use-after-free in socket filter code, in order to handle the fact that listener lock is no longer taken during the three-way TCP handshake. From Eric Dumazet. 13) Fix infoleak in RTM_GETSTATS, from Nikolay Aleksandrov. 14) Fix tail call generation in x86-64 BPF JIT, from Alexei Starovoitov. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (77 commits) net: 8021q: skip packets if the vlan is down bpf: fix bpf_tail_call() x64 JIT net: stmmac: dwmac-rk: Add RK3128 GMAC support rndis_host: support Novatel Verizon USB730L net: rtnetlink: fix info leak in RTM_GETSTATS call socket, bpf: fix possible use after free mlxsw: spectrum_router: Track RIF of IPIP next hops mlxsw: spectrum_router: Move VRF refcounting net: hns3: Fix an error handling path in 'hclge_rss_init_hw()' net: mvpp2: Fix clock resource by adding an optional bus clock r8152: add Linksys USB3GIGV1 id l2tp: fix l2tp_eth module loading ip_gre: erspan device should keep dst ip_gre: set tunnel hlen properly in erspan_tunnel_init ip_gre: check packet length and mtu correctly in erspan_xmit ip_gre: get key from session_id correctly in erspan_rcv tipc: use only positive error codes in messages ppp: fix __percpu annotation udp: perform source validation for mcast early demux IPv4: early demux can return an error code ...
2017-10-04bpf: enforce return code for cgroup-bpf programsAlexei Starovoitov
with addition of tnum logic the verifier got smart enough and we can enforce return codes at program load time. For now do so for cgroup-bpf program types. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04bpf: introduce BPF_PROG_QUERY commandAlexei Starovoitov
introduce BPF_PROG_QUERY command to retrieve a set of either attached programs to given cgroup or a set of effective programs that will execute for events within a cgroup Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> for cgroup bits Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04bpf: multi program support for cgroup+bpfAlexei Starovoitov
introduce BPF_F_ALLOW_MULTI flag that can be used to attach multiple bpf programs to a cgroup. The difference between three possible flags for BPF_PROG_ATTACH command: - NONE(default): No further bpf programs allowed in the subtree. - BPF_F_ALLOW_OVERRIDE: If a sub-cgroup installs some bpf program, the program in this cgroup yields to sub-cgroup program. - BPF_F_ALLOW_MULTI: If a sub-cgroup installs some bpf program, that cgroup program gets run in addition to the program in this cgroup. NONE and BPF_F_ALLOW_OVERRIDE existed before. This patch doesn't change their behavior. It only clarifies the semantics in relation to new flag. Only one program is allowed to be attached to a cgroup with NONE or BPF_F_ALLOW_OVERRIDE flag. Multiple programs are allowed to be attached to a cgroup with BPF_F_ALLOW_MULTI flag. They are executed in FIFO order (those that were attached first, run first) The programs of sub-cgroup are executed first, then programs of this cgroup and then programs of parent cgroup. All eligible programs are executed regardless of return code from earlier programs. To allow efficient execution of multiple programs attached to a cgroup and to avoid penalizing cgroups without any programs attached introduce 'struct bpf_prog_array' which is RCU protected array of pointers to bpf programs. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> for cgroup bits Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "A lot of stuff, sorry about that. A week on a beach, then a bunch of time catching up then more time letting it bake in -next. Shan't do that again!" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (51 commits) include/linux/fs.h: fix comment about struct address_space checkpatch: fix ignoring cover-letter logic m32r: fix build failure lib/ratelimit.c: use deferred printk() version kernel/params.c: improve STANDARD_PARAM_DEF readability kernel/params.c: fix an overflow in param_attr_show kernel/params.c: fix the maximum length in param_get_string mm/memory_hotplug: define find_{smallest|biggest}_section_pfn as unsigned long mm/memory_hotplug: change pfn_to_section_nr/section_nr_to_pfn macro to inline function kernel/kcmp.c: drop branch leftover typo memremap: add scheduling point to devm_memremap_pages mm, page_alloc: add scheduling point to memmap_init_zone mm, memory_hotplug: add scheduling point to __add_pages lib/idr.c: fix comment for idr_replace() mm: memcontrol: use vmalloc fallback for large kmem memcg arrays kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv() include/linux/bitfield.h: remove 32bit from FIELD_GET comment block lib/lz4: make arrays static const, reduces object code size exec: binfmt_misc: kill the onstack iname[BINPRM_BUF_SIZE] array exec: binfmt_misc: fix race between load_misc_binary() and kill_node() ...
2017-10-04Merge tag 'trace-v4.14-rc1-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixlets from Steven Rostedt: "Two updates: - A memory fix with left over code from spliting out ftrace_ops and function graph tracer, where the function graph tracer could reset the trampoline pointer, leaving the old trampoline not to be freed (memory leak). - The update to Paul's patch that added the unnecessary READ_ONCE(). This removes the unnecessary READ_ONCE() instead of having to rebase the branch to update the patch that added it" * tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}() ftrace: Fix kmemleak in unregister_ftrace_graph
2017-10-04watchdog/core: Put softlockup_threads_initialized under ifdef guardThomas Gleixner
The variable is unused when the softlockup detector is disabled in Kconfig. Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-10-04watchdog/core: Rename some softlockup_* functionsThomas Gleixner
The function names made sense up to the point where the watchdog (re)configuration was unified to use softlockup_reconfigure_threads() for all configuration purposes. But that includes scenarios which solely configure the nmi watchdog. Rename softlockup_reconfigure_threads() and softlockup_init_threads() so the function names match the functionality. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linuxfoundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com>
2017-10-04powerpc/watchdog: Make use of watchdog_nmi_probe()Thomas Gleixner
The rework of the core hotplug code triggers the WARN_ON in start_wd_cpu() on powerpc because it is called multiple times for the boot CPU. The first call is via: start_wd_on_cpu+0x80/0x2f0 watchdog_nmi_reconfigure+0x124/0x170 softlockup_reconfigure_threads+0x110/0x130 lockup_detector_init+0xbc/0xe0 kernel_init_freeable+0x18c/0x37c kernel_init+0x2c/0x160 ret_from_kernel_thread+0x5c/0xbc And then again via the CPU hotplug registration: start_wd_on_cpu+0x80/0x2f0 cpuhp_invoke_callback+0x194/0x620 cpuhp_thread_fun+0x7c/0x1b0 smpboot_thread_fn+0x290/0x2a0 kthread+0x168/0x1b0 ret_from_kernel_thread+0x5c/0xbc This can be avoided by setting up the cpu hotplug state with nocalls and move the initialization to the watchdog_nmi_probe() function. That initializes the hotplug callbacks without invoking the callback and the following core initialization function then configures the watchdog for the online CPUs (in this case CPU0) via softlockup_reconfigure_threads(). Reported-and-tested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: linuxppc-dev@lists.ozlabs.org
2017-10-04watchdog/core, powerpc: Lock cpus across reconfigurationThomas Gleixner
Instead of dropping the cpu hotplug lock after stopping NMI watchdog and threads and reaquiring for restart, the code and the protection rules become more obvious when holding cpu hotplug lock across the full reconfiguration. Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1710022105570.2114@nanos
2017-10-04watchdog/core, powerpc: Replace watchdog_nmi_reconfigure()Thomas Gleixner
The recent cleanup of the watchdog code split watchdog_nmi_reconfigure() into two stages. One to stop the NMI and one to restart it after reconfiguration. That was done by adding a boolean 'run' argument to the code, which is functionally correct but not necessarily a piece of art. Replace it by two explicit functions: watchdog_nmi_stop() and watchdog_nmi_start(). Fixes: 6592ad2fcc8f ("watchdog/core, powerpc: Make watchdog_nmi_reconfigure() two stage") Requested-by: Linus 'Nursing his pet-peeve' Torvalds <torvalds@linuxfoundation.org> Signed-off-by: Thomas 'Mopping up garbage' Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Don Zickus <dzickus@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1710021957480.2114@nanos
2017-10-03kernel/params.c: improve STANDARD_PARAM_DEF readabilityJean Delvare
Align the parameters passed to STANDARD_PARAM_DEF for clarity. Link: http://lkml.kernel.org/r/20170928162728.756143cc@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Suggested-by: Ingo Molnar <mingo@kernel.org> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: fix an overflow in param_attr_showJean Delvare
Function param_attr_show could overflow the buffer it is operating on. The buffer size is PAGE_SIZE, and the string returned by attribute->param->ops->get is generated by scnprintf(buffer, PAGE_SIZE, ...) so it could be PAGE_SIZE - 1 long, with the terminating '\0' at the very end of the buffer. Calling strcat(..., "\n") on this isn't safe, as the '\0' will be replaced by '\n' (OK) and then another '\0' will be added past the end of the buffer (not OK.) Simply add the trailing '\n' when writing the attribute contents to the buffer originally. This is safe, and also faster. Credits to Teradata for discovering this issue. Link: http://lkml.kernel.org/r/20170928162602.60c379c7@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: fix the maximum length in param_get_stringJean Delvare
The length parameter of strlcpy() is supposed to reflect the size of the target buffer, not of the source string. Harmless in this case as the buffer is PAGE_SIZE long and the source string is always much shorter than this, but conceptually wrong, so let's fix it. Link: http://lkml.kernel.org/r/20170928162515.24846b4f@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Ingo Molnar <mingo@kernel.org> Cc: Baoquan He <bhe@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/kcmp.c: drop branch leftover typoCyrill Gorcunov
The else branch been left over and escaped the source code refresh. Not a problem but better clean it up. Fixes: 0791e3644e5e ("kcmp: add KCMP_EPOLL_TFD mode to compare epoll target files") Link: http://lkml.kernel.org/r/20170917165838.GA1887@uranus.lan Reported-by: Eugene Syromiatnikov <esyr@redhat.com> Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Andrei Vagin <avagin@virtuozzo.com> Cc: Pavel Emelyanov <xemul@virtuozzo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03memremap: add scheduling point to devm_memremap_pagesMichal Hocko
devm_memremap_pages is initializing struct pages in for_each_device_pfn and that can take quite some time. We have even seen a soft lockup triggering on a non preemptive kernel NMI watchdog: BUG: soft lockup - CPU#61 stuck for 22s! [kworker/u641:11:1808] [...] RIP: 0010:[<ffffffff8118b6b7>] [<ffffffff8118b6b7>] devm_memremap_pages+0x327/0x430 [...] Call Trace: pmem_attach_disk+0x2fd/0x3f0 [nd_pmem] nvdimm_bus_probe+0x64/0x110 [libnvdimm] driver_probe_device+0x1f7/0x420 bus_for_each_drv+0x52/0x80 __device_attach+0xb0/0x130 bus_probe_device+0x87/0xa0 device_add+0x3fc/0x5f0 nd_async_device_register+0xe/0x40 [libnvdimm] async_run_entry_fn+0x43/0x150 process_one_work+0x14e/0x410 worker_thread+0x116/0x490 kthread+0xc7/0xe0 ret_from_fork+0x3f/0x70 fix this by adding cond_resched every 1024 pages. Link: http://lkml.kernel.org/r/20170918121410.24466-4-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Reported-by: Johannes Thumshirn <jthumshirn@suse.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Cc: Dan Williams <dan.j.williams@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/sysctl.c: remove duplicate UINT_MAX check on do_proc_douintvec_conv()Luis R. Rodriguez
do_proc_douintvec_conv() has two UINT_MAX checks, we can remove one. This has no functional changes other than fixing a compiler warning: kernel/sysctl.c:2190]: (warning) Identical condition '*lvalp>UINT_MAX', second condition is always false Fixes: 4f2fec00afa60 ("sysctl: simplify unsigned int support") Link: http://lkml.kernel.org/r/20170919072918.12066-1-mcgrof@kernel.org Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Reported-by: David Binderman <dcb314@hotmail.com> Acked-by: Kees Cook <keescook@chromium.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03android: binder: drop lru lock in isolate callbackSherry Yang
Drop the global lru lock in isolate callback before calling zap_page_range which calls cond_resched, and re-acquire the global lru lock before returning. Also change return code to LRU_REMOVED_RETRY. Use mmput_async when fail to acquire mmap sem in an atomic context. Fix "BUG: sleeping function called from invalid context" errors when CONFIG_DEBUG_ATOMIC_SLEEP is enabled. Also restore mmput_async, which was initially introduced in commit ec8d7c14ea14 ("mm, oom_reaper: do not mmput synchronously from the oom reaper context"), and was removed in commit 212925802454 ("mm: oom: let oom_reap_task and exit_mmap run concurrently"). Link: http://lkml.kernel.org/r/20170914182231.90908-1-sherryy@android.com Fixes: f2517eb76f1f2 ("android: binder: Add global lru shrinker to binder") Signed-off-by: Sherry Yang <sherryy@android.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reported-by: Kyle Yan <kyan@codeaurora.org> Acked-by: Arve Hjønnevåg <arve@android.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Martijn Coenen <maco@google.com> Cc: Todd Kjos <tkjos@google.com> Cc: Riley Andrews <riandrews@android.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Hillf Danton <hdanton@sina.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Hoeun Ryu <hoeun.ryu@gmail.com> Cc: Christopher Lameter <cl@linux.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03kernel/params.c: align add_sysfs_param documentation with codeJean Delvare
This parameter is named kp, so the documentation should use that. Fixes: 9b473de87209 ("param: Fix duplicate module prefixes") Link: http://lkml.kernel.org/r/20170919142656.64aea59e@endymion Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-03bpf: fix bpf_tail_call() x64 JITAlexei Starovoitov
- bpf prog_array just like all other types of bpf array accepts 32-bit index. Clarify that in the comment. - fix x64 JIT of bpf_tail_call which was incorrectly loading 8 instead of 4 bytes - tighten corresponding check in the interpreter to stay consistent The JIT bug can be triggered after introduction of BPF_F_NUMA_NODE flag in commit 96eabe7a40aa in 4.14. Before that the map_flags would stay zero and though JIT code is wrong it will check bounds correctly. Hence two fixes tags. All other JITs don't have this problem. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Fixes: 96eabe7a40aa ("bpf: Allow selecting numa node during map creation") Fixes: b52f00e6a715 ("x86: bpf_jit: implement bpf_tail_call() helper") Acked-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-03Merge branch 'for-4.14-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fix from Tejun Heo: "The recent migration code updates assumed that migrations always execute from the top to the bottom once and didn't clean up internal states after each migration round; however, cgroup_transfer_tasks() repeats the inner steps multiple times and the garbage internal states from the previous iteration led to OOPS. Waiman fixed the bug by reinitializing the relevant states at the end of each migration round" * 'for-4.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: Reinit cgroup_taskset structure before cgroup_migrate_execute() returns
2017-10-03rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}()Paul E. McKenney
The read of ->dynticks_nmi_nesting in rcu_irq_enter() and rcu_irq_exit() is currently protected with READ_ONCE(). However, this protection is unnecessary because (1) ->dynticks_nmi_nesting is updated only by the current CPU, (2) Although NMI handlers can update this field, they reset it back to its old value before return, and (3) Interrupts are disabled, so nothing else can modify it. The value of ->dynticks_nmi_nesting is thus effectively constant, and so no protection is required. This commit therefore removes the READ_ONCE() protection from these two accesses. Link: http://lkml.kernel.org/r/20170926031902.GA2074@linux.vnet.ibm.com Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-03ftrace: Fix kmemleak in unregister_ftrace_graphShu Wang
The trampoline allocated by function tracer was overwriten by function_graph tracer, and caused a memory leak. The save_global_trampoline should have saved the previous trampoline in register_ftrace_graph() and restored it in unregister_ftrace_graph(). But as it is implemented, save_global_trampoline was only used in unregister_ftrace_graph as default value 0, and it overwrote the previous trampoline's value. Causing the previous allocated trampoline to be lost. kmmeleak backtrace: kmemleak_vmalloc+0x77/0xc0 __vmalloc_node_range+0x1b5/0x2c0 module_alloc+0x7c/0xd0 arch_ftrace_update_trampoline+0xb5/0x290 ftrace_startup+0x78/0x210 register_ftrace_function+0x8b/0xd0 function_trace_init+0x4f/0x80 tracing_set_tracer+0xe6/0x170 tracing_set_trace_write+0x90/0xd0 __vfs_write+0x37/0x170 vfs_write+0xb2/0x1b0 SyS_write+0x55/0xc0 do_syscall_64+0x67/0x180 return_from_SYSCALL_64+0x0/0x6a [ Looking further into this, I found that this was left over from when the function and function graph tracers shared the same ftrace_ops. But in commit 5f151b2401 ("ftrace: Fix function_profiler and function tracer together"), the two were separated, and the save_global_trampoline no longer was necessary (and it may have been broken back then too). -- Steven Rostedt ] Link: http://lkml.kernel.org/r/20170912021454.5976-1-shuwang@redhat.com Cc: stable@vger.kernel.org Fixes: 5f151b2401 ("ftrace: Fix function_profiler and function tracer together") Signed-off-by: Shu Wang <shuwang@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-10-01Merge branch 'smp-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull smp/hotplug fixes from Thomas Gleixner: "This addresses the fallout of the new lockdep mechanism which covers completions in the CPU hotplug code. The lockdep splats are false positives, but there is no way to annotate that reliably. The solution is to split the completions for CPU up and down, which requires some reshuffling of the failure rollback handling as well" * 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: smp/hotplug: Hotplug state fail injection smp/hotplug: Differentiate the AP completion between up and down smp/hotplug: Differentiate the AP-work lockdep class between up and down smp/hotplug: Callback vs state-machine consistency smp/hotplug: Rewrite AP state machine core smp/hotplug: Allow external multi-instance rollback smp/hotplug: Add state diagram
2017-10-01Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "The scheduler pull request comes with the following updates: - Prevent a divide by zero issue by validating the input value of sysctl_sched_time_avg - Make task state printing consistent all over the place and have explicit state characters for IDLE and PARKED so they wont be displayed as 'D' state which confuses tools" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/sysctl: Check user input value of sysctl_sched_time_avg sched/debug: Add explicit TASK_PARKED printing sched/debug: Ignore TASK_IDLE for SysRq-W sched/debug: Add explicit TASK_IDLE printing sched/tracing: Use common task-state helpers sched/tracing: Fix trace_sched_switch task-state printing sched/debug: Remove unused variable sched/debug: Convert TASK_state to hex sched/debug: Implement consistent task-state printing
2017-10-01Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Thomas Gleixner: - Prevent a division by zero in the perf aux buffer handling - Sync kernel headers with perf tool headers - Fix a build failure in the syscalltbl code - Make the debug messages of perf report --call-graph work correctly - Make sure that all required perf files are in the MANIFEST for container builds - Fix the atrr.exclude kernel handling so it respects the perf_event_paranoid and the user permissions - Make perf test on s390x work correctly * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/aux: Only update ->aux_wakeup in non-overwrite mode perf test: Fix vmlinux failure on s390x part 2 perf test: Fix vmlinux failure on s390x perf tools: Fix syscalltbl build failure perf report: Fix debug messages with --call-graph option perf evsel: Fix attr.exclude_kernel setting for default cycles:p tools include: Sync kernel ABI headers with tooling headers perf tools: Get all of tools/{arch,include}/ in the MANIFEST
2017-10-01Merge branch 'locking-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking fixes from Thomas Gleixner: "Two fixes for locking: - Plug a hole the pi_stat->owner serialization which was changed recently and failed to fixup two usage sites. - Prevent reordering of the rwsem_has_spinner() check vs the decrement of rwsem count in up_write() which causes a missed wakeup" * 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: locking/rwsem-xadd: Fix missed wakeup due to reordering of load futex: Fix pi_state->owner serialization
2017-10-01Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: - Add a missing NULL pointer check in free_irq() - Fix a memory leak/memory corruption in the generic irq chip - Add missing rcu annotations for radix tree access - Use ffs instead of fls when extracting data from a chip register in the MIPS GIC irq driver - Fix the unmasking of IPI interrupts in the MIPS GIC driver so they end up at the target CPU and not at CPU0 * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irq/generic-chip: Don't replace domain's name irqdomain: Add __rcu annotations to radix tree accessors irqchip/mips-gic: Use effective affinity to unmask irqchip/mips-gic: Fix shifts to extract register fields genirq: Check __free_irq() return value for NULL
2017-10-01bpf: Fix compiler warning on info.map_ids for 32bit platformMartin KaFai Lau
This patch uses u64_to_user_ptr() to cast info.map_ids to a userspace ptr. It also tags the user_map_ids with '__user' for sparse check. Fixes: cb4d2b3f03d8 ("bpf: Add name, load_time, uid and map_ids to bpf_prog_info") Signed-off-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-29Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull waitid fix from Al Viro: "Fix infoleak in waitid()" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: fix infoleak in waitid(2)
2017-09-29fix infoleak in waitid(2)Al Viro
kernel_waitid() can return a PID, an error or 0. rusage is filled in the first case and waitid(2) rusage should've been copied out exactly in that case, *not* whenever kernel_waitid() has not returned an error. Compat variant shares that braino; none of kernel_wait4() callers do, so the below ought to fix it. Reported-and-tested-by: Alexander Potapenko <glider@google.com> Fixes: ce72a16fa705 ("wait4(2)/waitid(2): separate copying rusage to userland") Cc: stable@vger.kernel.org # v4.13 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>